Development and evaluation of lessons for class and group situations in grade one

Thesis (Ed.M.)--Boston Universit

Differences in salivary α-amylase levels among women with different taste sensitivities

Saliva is the main component of taste receptor cells external environment, and consequently it may have a decisive role in taste perception. Taste sensitivity varies among different individuals. Sensitivity to the compound n-6-propylthiouracil (PROP) has been considerably studied and besides the known influence of genetic background, the contribution of perireceptor environment is not completely clear yet. Salivary α-amylase (one of the main proteins of saliva) is involved in carbohydrate digestion and its enzymatic activity may change the levels of sugars present in the mouth, influencing food perception. To evaluate differences in salivary total protein content and α-amylase activity and expression among individuals with different PROP taste sensitivities. Sixty seven female women (18-30 years old) were classified in one of the three groups of taste sensitivity (non-taster, medium-taster or super-taster), according to the perceived intensity for PROP, using Labeled Magnitude Scales. Saliva was collected without stimulation. Flow rate was calculated by dividing total volume for the 5 minutes collection. Bradford method was used for total protein assessment. Dinitrosalicylic acid assay was used for measuring the starch-hydrolyzing activity of salivary α-amylase, while the expression of this enzyme was evaluated by Wester blot. 20,9% of the subjects were classified as non-taters. The three groups presented similar saliva flow rates and total protein content was not significantly different although a tendency for lower protein concentration in medium-tasters individuals was observed. Salivary α-amylase activity (U/min) was higher in supertasters (P<0,05). Salivary α-amylase activity (U/min) was higher in super-tasters (P<0,05) without any significant differences in expression. In women individual differences in saliva composition can contribute to the different taste sensitivity. One of the differences appears to be α-amylase enzymatic activity. The reason for this deserves to be elucidated, as well as the potential involvement of others salivary proteins

Microstructural characterization and tribocorrosion behaviour of Al/Al3Ti and Al/Al3Zr FGMs

Al/Al3Ti and Al/Al3Zr functionally graded materials (FGMs) were manufactured through a centrifugal method from Al–5 mass % Ti and Al–5 mass % Zr, respectively. Applied centrifugal forces were 30, 60 and 120 G (units of gravity). Microstructural characterization was performed and the influence of the reinforcing phase on the tribocorrosion behaviour of the FGMs was investigated. An increase in both the particles volume fraction as well as their orientation in the outer regions of the FGMs was found as the applied centrifugal force increased. Better tribocorrosion behaviour was found in the samples containing the highest concentration of reinforcing particles. However the microstructure below the surface appears to influence the tribocorrosion behaviour.The authors gratefully acknowledge the financial support provided by "Tokai Region Nanotechnology Manufacturing Cluster in KNOWLEDGE CLUSTER INITIATIVE" by the Ministry of Education, Culture, Sports, Science and Technology of Japan. Acknowledgments are also due to "FCT", Portugal, through the project SFRH/BPD/5518/2001

Have historical land use/land cover changes triggered a fire regime shift in central Spain?

Fire is one of the main disturbance factors shaping the landscape, and landscape is a key driver of fire behavior. Considering the role played by land use and land cover (LULC) changes as the main driver of landscape dynamics, the aim of this study was to calculate and analyze (i) the real impact of fire on LULC changes and (ii) how these LULC changes were influencing the fire regime. We used methods of historical geography and socio-spatial systemic analysis for reconstructing and assessing the LULC change and fire history in six case studies in the Central Mountain System (Spain) from archival documentary sources and historical cartography. The main result is an accurate dataset of fire records from 1497 to 2013 and a set of LULC maps for three time points (1890s–1930s, 1956–1957, and the 2000s). We have shown the nonlinear evolution of the fire regime and the importance of the local scale when assessing the interaction of landscape dynamics and fire regime variation. Our findings suggest that LULC trends have been the main influencing factor of fire regime variation in Central Spain since the mid-19th centuryinfo:eu-repo/semantics/publishedVersio

Electrodeposition of Zn-Mn alloys from recycling battery leach solutions in the presence of amines

The recovery of metal ions by electrodeposition from solutions resulting from the lixiviation of spent Zn-MnO2 batteries was studied. It was attempted to optimise the electrodeposition process, the selectivity of ion-separation, the morphologic characteristics, and the anticorrosive and galvanic properties of metallic deposits. The simultaneous deposition of zinc and manganese on different ferrous substrates under various experimental conditions was tested. This allowed us to access the efficiency of the electrodeposition, the morphology and composition of the metallic deposits, as well as their performance as galvanic coating layers. The effect of amine additives, namely, of methylamine and ethylenediamine, on the properties of the coatings was also studied. It was shown that the amines with buffering or passivating effects improve the simultaneous deposition of Mn

Microscopy techniques for dye distribution in DSCs nanocrystalline TiO2 films

Capture of sunlight has attracted an increasing interest in the scientific community and triggered the development of efficient and cheap photovoltaic devices. Amongst recent generation technologies for solar energy conversion, dye-sensitized solar cells (DSCs) show an optimal trade-off between high-conversion efficiency and low-cost manufacturing. For the last two decades, significant progress has been made and best energy conversion efficiency of the DSC at the laboratory scale has surpassed 12% [1]. A lot of work has focused on the enlargement of surface areas to enhance the amount of adsorbed dyes by reduction of nanoparticle sizes or utilization of novel structures. Nevertheless there remain some crucial details of DSC operation for which limited information is available, namely dye diffusion and adsorption, surface coverage and dye distribution throughout the nc-TiO2 film. Microprobe techniques can be powerful tools to evaluate the dye load, the dye distribution and dye depth profile in sensitized films. Electron Probe Microanalysis (EPMA) and Ion Beam Analytical (IBA) techniques using a micro-ion beam, namely micro-Particle Induced X-ray Emission ( PIXE) and Rutherford Backscattering Spectrometry (RBS), were used to quantify and to study the distribution of the ruthenium organometallic (N719) dye in TiO2 films, profiting from the different penetration depth and beam sizes of each technique. Two different types of films were prepared and sensitized, mesoporous nanoparticles and 1D nanostructured TiO2 films (figure 1). Despite the low concentration of Ru, the high sensitive analytical techniques used allowed to assess the Ru surface distribution and depth profile. Fig. 2 shows the PIXE maps of Ru and Ti indicating an homogeneous surface distribution. The same figure presents the RBS spectra obtained with a 2 MeV proton beam of the same sample showing that a good spectra fit is obtained considering only two sample layers: the first one with a 1.7 ìm thickness; the second one being the SiO2 substrate. The Ru RBS signal also shows that the dye has an homogeneous depth distribution. Due to the fine spatial resolution of the EPMA/WDS (Wavelength Dispersive Spectroscopy) technique it was possible to visualise the dye distribution in sample cross-section (with micrometer or submicrometer dimensions) as presented in Fig. 3 for the elemental mapping of a mesoporous nanoparticle TiO2 film. Dye load evaluation by two different techniques (ìPIXE and EPMA/WDS) provided similar results (Ru/Ti values around 0.5 %). The distribution analysis of the organometallic dye (N719) was done through ruthenium distribution via X-ray mapping. RBS was used to assess the ruthenium depth profile. This assessment can lead to a better understanding of the device performance

Analysis of acids and sugars in fruit-based drinks by SEC-UV-RI

Beverage industry produces a large and diverse range of soft drinks, beverages containing flavorings and/or fruit juices (sodas and fruit juices), of which the quality and safety must be monitored to protect and satisfy customers. From the raw ingredients to the final product, quality control is needed to ensure product safety, quality, labelling, regulatory compilance and consistency. The development of analytical techniques for simultaneous analysis of different compounds essential to control the product quality, as an alternative to several independent traditional reference methods, is of major importance. Therefore, the present work reports the application of size exclusion chromatography (SEC), which allows carrying out analysis free of organic solvents, using two detectors coupled in series - Ultraviolet (UV) and Refractive Index (RI) - for the simultaneous analysis of acidifiers (citric, tartaric, lactic, acetic, malic and ascorbic acids, by UV), and sweeteners (sucrose, glucose and fructose by RI), in commercial non-alcoholic beverages with different levels of added fruit juice. Ascorbic acid is used as a stabilizer in the soft drinks, improving the beverage shelf-life stability due to its antioxidant properties. The results showed that the simultaneous calibrations for acid compounds (UV) and for glucose (RI) were straight-forward. On the other hand, for sucrose and fructose simultaneous analysis, the calibrations (RI) were more complex since the predictive models established had to take into account malic and tartaric acids interferences, regardless the good resolution between the peaks of sucrose and fructose. Finally, the results for sample analysis showed that all the sugars evaluated were present in the juice drinks as well as the citric, tartaric, malic and ascorbic acids. In all samples, lactic and acetic acids were not detected

Impacto da crise financeira e social na saúde mental

Preocupados com o impacto da crise nanceira e social na saúde mental das pessoas, neste artigo fazemos uma ref exão sobre as últimas evidências disponíveis sobre o tema em Portugal e no mundo, procurando recentrar a atenção dos pro ssionais de saúde mental, naquilo que necessita ser promovido: a centralidade dos cuidados nas pessoas e a continuidade dos cuidados em saúde mental. A instalação da crise financeira, que a todos apanhou desprevenidos, veio revelar as fragilidades e falta de preparação dos sistemas de saúde para lidar com problemas sociais que, frequentemente, constituem risco para o surgimento de psicopatologia. A forma como as famílias e as pessoas foram capazes de fazer face às suas necessidades, em termos de bem-estar, é também revelador da capacidade de adaptação e resiliência dos portugueses. A crise nanceira e social teve e continuará a ter consequências em várias dimensões da vida das pessoas, pelo que re etimos também sobre algumas estratégias para a minimização dos efeitos da crise na saúde mental das pessoas

CODAP: um Consenso Multidisciplinar sobre a Definição, Diagnóstico e Tratamento da Dislipidemia Aterogénica em Portugal

Introduction and aims: Atherogenic dyslipidemia is an important contributor to residual cardiovascular (CV) risk, but it is underdiagnosed and undertreated. This study aimed to assess the opinion of Portuguese experts to generate a consensus concerning the diagnosis and treatment of atherogenic dyslipidemia, as well as to contribute toward standardization of clinical practice in this disorder. Methods: The study consisted in the application of a questionnaire to an expert panel, following a modified Delphi methodology. Results: The majority (88.4%) of the proposed items were found to be consensual. The expert panel recognized the importance of the atherogenic dyslipidemia phenotype, the role played by low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol as risk markers and therapeutic targets, the choice of statins as first-line lipid-lowering drugs, and the value of associating statins with fenofibrate as a means to reduce residual CV risk. However, the role played by triglycerides in CV risk and the therapeutic value of fibrates lacked consensus. Taking into consideration the state of the art and the opinions expressed in this study, the scientific committee developed a treatment algorithm aimed to improve the perception and treatment of atherogenic dyslipidemia. Conclusions: The experts involved in this study were shown to be familiar with the concept and the importance of atherogenic dyslipidemia. The few situations in which a consensus could not be found were mainly related to the interpretation and/or relevance of the available evidence.info:eu-repo/semantics/publishedVersio